USA’s largest “carbon neutral” office set for San Diego

A tower block destined for San Diego will be the largest carbon-neutral office building in the United States, according to a press release put out in December by Hines, the project's developer.

Offices use energy more intensively than houses or schools, which are more typical candidates for carbon neutrality, so a carbon neutral office is ambitious in itself. But it's the size of the office block that sets this project apart. Named LPL Financial at La Jolla Commons after its eventual tenant, it joins existing Hines-developed offices at the La Jolla Commons campus in San Diego. The building will host 415,000 ft2 of office space, spread over 13 stories. As office blocks go, that's not enormous—New York’s 52-story 7 World Trade Center contains 1.7 million ft2 of premium office real estate—but it's a tall order as far as carbon neutrality is concerned.

Hines' claim is a straightforward one: the building will, averaged over the course of each year, produce more energy than it consumes. This basically matches the National Renewable Energy Laboratory’s definition of a Zero-Energy Building, provided that the energy is produced on site and comes from a non-polluting renewable source. But because LPL@LJC (to shorten the office block's name) uses natural gas as its sole source of energy, some have questioned, and even dismissed, Hines' net zero claims—despite the fact that the natural gas isn't actually combusted.

To avoid impinging the office's Class A spec, Hines hasn't, by its own admission, gone as far as it might in reducing LPL@LJC's energy consumption. "You can go sub-40 kBtus, but it can get costly and you may end up having to reduce glass and cutting out natural light," Hines’ Global Sustainability Officer Gary Holtzer told Forbes. "We wanted to do this without changing the class-A design." Here, "kBtus" is an industry colloquialism for kBtu per square foot per year, 1 Btu being a unit of energy roughly equivalent to a kilojoule. Forbes reports that the building's energy consumption will be 41.5 kBtu per square foot per year.

That's not to say that LPL@LJC will be without energy-saving tech. It is set to use under-floor air conditioning which, Hines' Senior Managing Director Paul Twardowski told Ars, allows cool air to be delivered at a slightly higher temperature, but at reduced velocity and pressure, than when delivered by overhead duct. In fact, ductwork and secondary motors are largely avoided. All in, the air conditioning will use less energy than a conventional system. The need for AC will be reduced, Hines claims, because the windows will come with a low-emissivity layer designed to reduce problematic heat from the sun.

Hines' approach to energy reduction may be somewhat conservative, but this poses little threat to the building's carbon neutrality; at least, not as Hines defines it. The company is effectively throwing generation technology at the problem. LPL@LJC's entire energy demand will be met electrically, using three parking space-sized Bloom Energy fuel cells, aka Bloom Boxes. Collectively they're capable of generating 5 million kWh of electricity per year. This is more electricity than Hines thinks the building will use. The patented fuel cells take natural gas and generate electricity using a "clean electro-chemical process" which Bloom Energy prefers not to discuss in detail. How clean? Hines claims that the cells produce about half the CO2 emissions of a natural gas power station.

But if the fuel cells emit any CO2, how can the building claim carbon neutrality? Hines intends to buy directed biogas from sources such as water treatment facilities, landfills, and livestock farms—greenhouse gases that would otherwise be released into the atmosphere. Yet the issue is muddied by the fact that the US does not yet have a distribution network dedicated to a biogas. The building will actually run on normal gas, but it will offset what it uses with biogas, introduced into the same networks that feed it where possible.

That may seem ambiguous, but Hines is unequivocal in its project FAQ. "We are placing a new 415,000-square-foot office building into service, filled with workers and releasing no new CO2 to the atmosphere."

Strictly speaking, LPL@LJC may well qualify as a carbon neutral building (though the CO2 released during the building's construction is disregarded). Whether it's in the true spirit of a National Renewable Energy Laboratory Zero Energy Building is more questionable. NREL's 2006 discussion (PDF) sets out a design hierarchy which prioritizes energy efficiency followed by on-site supply. Shipping (or piping) in renewable energy sources for on-site generation, or purchasing remotely generated renewable energy, come further down the hierarchy.

But for openness, Hines deserves some credit. The company has set out what it means by net zero, and has explained, openly, how it intends to achieve it.

Promoted Comments

Architectural designer here. I'm not involved with this project at all, but perhaps I can answer some questions.

With regard to "carbon neutral" as an accurate descriptor, that looks like a valid criticism here. I don't see any mention in the press release of LEED or Energy Star certification, or (in a quick skimming) any sort of third-party validation at all. Most of those systems require fairly strict prescriptive approaches, as well as post-construction validation of energy use. LEED in particular also attempts to account for carbon emission in the production and transportation of building materials -- the former can be significant, but the latter is surprisingly marginal, amortized over the life of the building -- as well as siting and public transit availability. There is also some accounting for total lifecycle waste and emissions. These systems can be games (and in truth they often are) but they at least offer some accountability.

The press release also mentions daylighting, but as another poster alluded to, natural lighting is increasingly less useful as an energy efficiency strategy. There are now high-quality and sophisticated fluorescent and LED lighting systems on the market. As a result, it's actually become more energy efficient to light spaces artificially than naturally, because the poor insulating value of windows now outweighs the amount of light they allow into the building. Windows also provide critical aesthetic and psychological benefits, but we try to limit glazing area to around 40% of the total wall area in a high-efficiency building.

As a last point, I find the choice of gas-fired fuel cells over photovoltaics a puzzling choice, even more so in a climate like La Jolla. According to the data I've dug up, three out of four days in La Jolla are sunny, and the cost per kW for PV systems is ludicrously low these days. An office tower is also an ideal choice for solar, since its hours of operation coincide with daylight hours, and off-peak use is minimal. It seems to me like Hines is playing games for PR points, rather than making any real stab at sustainability.

We can nitpick their claim, but it's better than 99.9% of the office buildings out there.

I toured a building like this in Minneapolis a few years ago. Really cool. A lot of glass, like the one in the article, to reduce artificial lighting needs. It had solar panels and even a wind turbine.

"Weeelll, technically he's zero carbon emissions if he uses biogas, but that's not technically no emitions, and when biogas isn't available they'll use natural gas, [next complaint], [next complaint], [next complaint]..." I'll admit, this guy is being a little disingenuous by claiming carbon neutrality, but if other businesses hear about how they're using SOFCs, maybe they'll see the success and get their own. Suddenly, an emerging market comes up for biogas. It's the chicken and the egg quandary. Sure, this technology can use biogas if it's available, but there's not going to be a supply of biogas until there's a market. Why not create the market and resign to the fact that you may have to use some carbons to bridge the gap?

If you want to chide the developer for claiming carbon neutrality while not actually being carbon neutral, that's fine; I totally agree that he's stretching the truth with his claims and slathering all his press releases with hype and marketing. Let's have a little more talk of the technology instead of how technically right or wrong the marketing is.

It is set to use under-floor air conditioning which... allows cool air to be delivered at a slightly higher temperature, but at reduced velocity and pressure, than when delivered by overhead duct. In fact, ductwork and secondary motors are largely avoided.

Does this actually work? I would expect that, since heat rises, delivering cool air at floor level would result in stratification where the cool air stays low and the air at torso height stays warm. Unless you use fans for mixing the air, which would cancel out the advantage regarding secondary motors.

The last place I lived had "radiant ceilings" which made equally little sense, delivering heat at ceiling level. I would think you optimally should deliver cool air at ceiling level and heat at floor level.

The last place I lived had "radiant ceilings" which made equally little sense, delivering heat at ceiling level. I would think you optimally should deliver cool air at ceiling level and heat at floor level.

Can't speak for the author, but I can say that I react negatively when I see equivocation like what appears to be going on regarding this building's "carbon neutral" status.

Any time a "good thing"™ is co-opted and made ambiguous and meaningless it's damaging to the movement.

There needs to be an actual EPA definition of what constitutes various levels of efficiency and what "carbon neutral" actually means, and a building that's doing anything other than producing at least as much real renewable energy as it uses IS NOT "carbon neutral".

It is set to use under-floor air conditioning which... allows cool air to be delivered at a slightly higher temperature, but at reduced velocity and pressure, than when delivered by overhead duct. In fact, ductwork and secondary motors are largely avoided.

Does this actually work? I would expect that, since heat rises, delivering cool air at floor level would result in stratification where the cool air stays low and the air at torso height stays warm. Unless you use fans for mixing the air, which would cancel out the advantage regarding secondary motors.

The trick is to keep the "thermocline" above the occupants' heads. It's much easier with high ceilings (as opposed to a normal residential building). You just have to include vents remove hot air from the top at some appropriate rate.

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The last place I lived had "radiant ceilings" which made equally little sense, delivering heat at ceiling level. I would think you optimally should deliver cool air at ceiling level and heat at floor level.

This works less well since we work near the floor and not the ceiling.

So does it also offset all the CO2 produced by employees and customers having to drive to its suburban location?

You should know better than that. "Carbon Neutral" and "Going Green" are just a few of the new feel good BS marketing terms companies are now using to gain PR points with the low information general public which sadly is a substantial number.

Can't speak for the author, but I can say that I react negatively when I see equivocation like what appears to be going on regarding this building's "carbon neutral" status.

Any time a "good thing"™ is co-opted and made ambiguous and meaningless it's damaging to the movement.

There needs to be an actual EPA definition of what constitutes various levels of efficiency and what "carbon neutral" actually means, and a building that's doing anything other than producing at least as much real renewable energy as it uses IS NOT "carbon neutral".

Exactly! These things are just companies capitalizing on the general public's desire to reduce their impact on the environment and they know that these same people will be more friendly towards and more likely to support these companies is they make meaningless claims like this. In the end it's about using people's guilt to promote themselves in a seemingly positive light.

We can nitpick their claim, but it's better than 99.9% of the office buildings out there.

I toured a building like this in Minneapolis a few years ago. Really cool. A lot of glass, like the one in the article, to reduce artificial lighting needs. It had solar panels and even a wind turbine.

I applaud their attempt to reduce their energy costs but that's all this really accomplishes.

Nearly every employee will be forced to drive a car to and from work. To be anywhere close to carbon neutral, or even "green" (whatever that means), this building would need to exist in a walkable neighborhood or at least in a neighborhood based upon public transit.

Think about it. How can we praise developments for using less energy when they're built in such a way that tons of energy must be used simply to access the building? Most people completely ignore this aspect, not ever considering how real estate development dictates energy usage far more than any other attribute of the buildings at question.

We can nitpick their claim, but it's better than 99.9% of the office buildings out there.

I toured a building like this in Minneapolis a few years ago. Really cool. A lot of glass, like the one in the article, to reduce artificial lighting needs. It had solar panels and even a wind turbine.

Energy consumption of transit to and from the building also should be considered. The following numbers are obviously not accurate but do illustrate the type of calculation that should be weighed.

Consider a building with a 1000 employees. If in a suburb where every employee commutes 15 miles each way in a vehicle that gets 30mpg, that's one gallon of gas per employee, or a 1000 gallons of gas per day.

Then compute the the total energy consumption of the building itself and energy consumption per employee. These numbers should be added together during most analyses, otherwise the results are not terribly useful.

When looking at only the building itself, and not the energy used during commuting, what we're left with is a narrow analysis of building technology. This is interesting from a scientific standpoint but is not represent the total carbon footprint of the building.

Perhaps an analogy would help make the point...

When buying a new home and looking at energy use/costs associated with each home, the energy efficiency of the home is only one factor. You could select or build the most energy efficient home in the world, but if it was necessary to drive 60 miles a day to and from work, living in that home is neither cheap nor energy efficient.

Nearly every employee will be forced to drive a car to and from work. To be anywhere close to carbon neutral, or even "green" (whatever that means), this building would need to exist in a walkable neighborhood or at least in a neighborhood based upon public transit.

Think about it. How can we praise developments for using less energy when they're built in such a way that tons of energy must be used simply to access the building? Most people completely ignore this aspect, not ever considering how real estate development dictates energy usage far more than any other attribute of the buildings at question.

This is all just a PR move. Anyone with a brain knows the label "Carbon Neutral" means nothing at all. Only the naive and the gullible think otherwise.

Clearly, as many of the above comments illustrate, you cannot segregate out one building's energy use from the rest of society's energy use in a meaningful way once you move outside the walls of the building. I think that's the fundamental source of the unease about the sort of claims to 'carbon neutrality' being made for this building and similar projects. Building a structure has not just first-order effects on energy use, but also second and third order effects. I seriously doubt any degree of analysis which doesn't model all of society and make decisions society-wide can sort out overall energy efficiency. What this points out is that the way our society has parsed itself up into institutions may not be well-suited to dealing with our energy problems. Of course we really know little about effective social engineering, so it is a thorny problem and even if we DID have a good handle on that the political issues are huge.

We can nitpick their claim, but it's better than 99.9% of the office buildings out there.

I toured a building like this in Minneapolis a few years ago. Really cool. A lot of glass, like the one in the article, to reduce artificial lighting needs. It had solar panels and even a wind turbine.

Energy consumption of transit to and from the building also should be considered. The following numbers are obviously not accurate but do illustrate the type of calculation that should be weighed.

Consider a building with a 1000 employees. If in a suburb where every employee commutes 15 miles each way in a vehicle that gets 30mpg, that's one gallon of gas per employee, or a 1000 gallons of gas per day.

Then compute the the total energy consumption of the building itself and energy consumption per employee. These numbers should be added together during most analyses, otherwise the results are not terribly useful.

When looking at only the building itself, and not the energy used during commuting, what we're left with is a narrow analysis of building technology. This is interesting from a scientific standpoint but is not represent the total carbon footprint of the building.

Perhaps an analogy would help make the point...

When buying a new home and looking at energy use/costs associated with each home, the energy efficiency of the home is only one factor. You could select or build the most energy efficient home in the world, but if it was necessary to drive 60 miles a day to and from work, living in that home is neither cheap nor energy efficient.

Context is a very important aspect when dealing with environmental sciences. I think that is why some of the people here commenting would like an EPA definition to "carbon neutral". You can link carbon neutrality or environmental impact to every step of the building process if you wanted to. Resource extraction from the earth, materials fabrication, construction equipment, land usage before the development. The list can go on and on.

If anything I think the comment about it being a technology display should be appreciated. Their scope on how carbon neutral may or may not be bullshit, but at least take a look at the technology and see how it is functioning.

Context is a very important aspect when dealing with environmental sciences. I think that is why some of the people here commenting would like an EPA definition to "carbon neutral". You can link carbon neutrality or environmental impact to every step of the building process if you wanted to. Resource extraction from the earth, materials fabrication, construction equipment, land usage before the development. The list can go on and on.

If anything I think the comment about it being a technology display should be appreciated. Their scope on how carbon neutral may or may not be bullshit, but at least take a look at the technology and see how it is functioning.

Agreed. This story should be framed as a precedent for a new energy source. That is a valid scope for analysis.

But if framed instead as a story about a carbon neutral building, the story is no longer educational. In fact, it is actively de-educating people if the scope doesn't include _all_ energy consumption required by use of the building.

So does it also offset all the CO2 produced by employees and customers having to drive to its suburban location?

That's not really fair -- how about if the building also offsets the CO2 that employee's produce when they breathe?

Also, employees would have to drive less to get to work if they worked in a suburban location by definition.

Google wrote:

sub·urb /ˈsəbərb/NounAn outlying district of a city, esp. a residential one.

Locating yourself in a suburban area is a fair critique. If we still lived and worked in urban environments we'd have a much smaller carbon footprint in general. Just imagine the energy savings from having your building up against other buildings on two sides...

Yet another office building with a floor to ceiling glass envelope. Natural light isn't an adequate excuse for building more wasteful glass boxes. The bottom three feet (at least) of each floor should be opaque. Glass below this level does not contribute meaningfully to outside views or natural lighting, but it does contribute to heat flux through the envelope.

Light shelves should be employed about 2-3 feet below the ceiling to increase the natural lighting effect, allowing for the reduction of clear glass while expanding the reach of natural light into the interior space and reducing glare by bouncing the light up onto the ceiling. In between the opaque lower section and the elevated light shelf, glass with tinted low-e coatings may be used to provide outside views while minimizing solar heat gain coefficient. The higher solar heat gain coefficient of the clear glass above the light shelf is partially mitigated by proximity to the ceiling return vents which exhaust the heat.

Nearly every employee will be forced to drive a car to and from work. To be anywhere close to carbon neutral, or even "green" (whatever that means), this building would need to exist in a walkable neighborhood or at least in a neighborhood based upon public transit.

Think about it. How can we praise developments for using less energy when they're built in such a way that tons of energy must be used simply to access the building? Most people completely ignore this aspect, not ever considering how real estate development dictates energy usage far more than any other attribute of the buildings at question.

That is total bullshit. Commuting structures are decided at the societal-level, not by the real estate developer. Tell me how Hines can build a building in Southern California where people won't get there by commuting? Or if you're not blaming the developer, tell me how San Diego can solve the commuting problem in a timeline such that LPL will have a building next year to house their employees.

The solution you are looking for requires long-term decisions and costs which are well beyond the scope of developing a single building. By all means, let's pursue those processes, but let's put the blame in the right place.

The title is carefully worded to only imply that this is the largest carbon neutral office in the USA. Does that imply that there is a larger carbon neutral office outside of the USA? So yes, what and where is it?

BTW, what will Apple's new campus be like from a carbon footprint standpoint?

We can nitpick their claim, but it's better than 99.9% of the office buildings out there.

I toured a building like this in Minneapolis a few years ago. Really cool. A lot of glass, like the one in the article, to reduce artificial lighting needs. It had solar panels and even a wind turbine.

Energy consumption of transit to and from the building also should be considered. The following numbers are obviously not accurate but do illustrate the type of calculation that should be weighed.

Consider a building with a 1000 employees. If in a suburb where every employee commutes 15 miles each way in a vehicle that gets 30mpg, that's one gallon of gas per employee, or a 1000 gallons of gas per day.

Then compute the the total energy consumption of the building itself and energy consumption per employee. These numbers should be added together during most analyses, otherwise the results are not terribly useful.

When looking at only the building itself, and not the energy used during commuting, what we're left with is a narrow analysis of building technology. This is interesting from a scientific standpoint but is not represent the total carbon footprint of the building.

Perhaps an analogy would help make the point...

When buying a new home and looking at energy use/costs associated with each home, the energy efficiency of the home is only one factor. You could select or build the most energy efficient home in the world, but if it was necessary to drive 60 miles a day to and from work, living in that home is neither cheap nor energy efficient.

Total bullshit.

If that's your analysis, then why stop at commuters' energy use? Why not include the energy use for the food eaten by the employees using that building? Or why not include the energy use from the plane flights that employees go on for vacation? Why not include the energy we're using in posting articles about the building?

Architectural designer here. I'm not involved with this project at all, but perhaps I can answer some questions.

With regard to "carbon neutral" as an accurate descriptor, that looks like a valid criticism here. I don't see any mention in the press release of LEED or Energy Star certification, or (in a quick skimming) any sort of third-party validation at all. Most of those systems require fairly strict prescriptive approaches, as well as post-construction validation of energy use. LEED in particular also attempts to account for carbon emission in the production and transportation of building materials -- the former can be significant, but the latter is surprisingly marginal, amortized over the life of the building -- as well as siting and public transit availability. There is also some accounting for total lifecycle waste and emissions. These systems can be games (and in truth they often are) but they at least offer some accountability.

The press release also mentions daylighting, but as another poster alluded to, natural lighting is increasingly less useful as an energy efficiency strategy. There are now high-quality and sophisticated fluorescent and LED lighting systems on the market. As a result, it's actually become more energy efficient to light spaces artificially than naturally, because the poor insulating value of windows now outweighs the amount of light they allow into the building. Windows also provide critical aesthetic and psychological benefits, but we try to limit glazing area to around 40% of the total wall area in a high-efficiency building.

As a last point, I find the choice of gas-fired fuel cells over photovoltaics a puzzling choice, even more so in a climate like La Jolla. According to the data I've dug up, three out of four days in La Jolla are sunny, and the cost per kW for PV systems is ludicrously low these days. An office tower is also an ideal choice for solar, since its hours of operation coincide with daylight hours, and off-peak use is minimal. It seems to me like Hines is playing games for PR points, rather than making any real stab at sustainability.

I'm also puzzled as to why they don't install PVs as well as their fuel cells. That said, biogas production and distribution infrastructure is a chicken-and-egg problem and it's going to take a significant number of buildings designed like this one to establish the demand level needed to get that infrastructure built out, so good on them for taking a first step toward that goal. Yes, it's a blatant PR move, but it's not without merit.

So, as a professional HVAC engineer who is really into (actually) green buildings, I feel compelled to provide a reality check:

- The energy claims of this building are based on models, not on actual performance. As anyone who works with computer models of any sort can tell you, models can and will lie to you. Diligence and skill are required to avoid that outcome. If there is an incentive to produce a certain result, then that caveat goes double.

- All green building performance rating systems, except for the Living Building Challenge (but including LEED) base their energy performance ratings on models. There is no requirement to provide real energy use information after the building is built, nor is there any mechanism for penalizing buildings who's actual energy use grossly exceeds that predicted by the model. There are a variety of reasons for this, some of them good, some of them not so much. But the upshot is that you have to take predicted building energy use figures with a great deal of skepticism.

- "You can go sub-40 kBtus, but it can get costly and you may end up having to reduce glass and cutting out natural light," This is typical architect bullshit. The first part is true: to get really good energy performance, you have to avoid making the building envelope entirely out of glass (duh!). (Yes, modern glass is very impressive. But really good glass is about as good as a really mediocre wall, from a thermal performance point of view. And glass that good is EXPENSIVE.)But the part about "cutting out natural light" is BS which springs from some combination of ignorance and a desire to justify a particular aesthetic. The fact of the matter is, you can have too much light as easily as too little. A good daylighting designer will tell you that you do not want or need large glass areas - good design means using the right amount of glass, in the right locations, to bring in natural light without creating glare. Glare is an enormous problem in buildings like this. Typically the occupant response is to keep the shades drawn 24/7 and use artificial light to compensate, thus ruining their views and increasing energy use still further. The building looks great from the outside, but it's pretty miserable for the occupants.

- Underfloor air distribution is not the same thing as displacement ventilation. Though underfloor systems can be displacement systems, they can also be designed for mixing (like normal overhead distribution). Likewise, you can use displacement ventilation without distributing air via the underfloor plenum - you use wall diffusers instead.Underfloor air distribution sounds like a good idea, but in practice does not work very well. The main problem is that you wind up picking up heat from the structure, so that the air warms up the further it gets from the point of injection. Some areas wind up with air that is too cold, while others wind up with air that is too warm. The solution to this is to put the air in ducts, but now you're basically back where you started (duct distribution) except it's generally much more expensive to distribute under the floor rather than overhead.Displacement ventilation, on the other hand, DOES work if properly implemented. Done correctly, it creates stratification such that the air temperature in the occupied zone (0-6' elevation) is cooler than the air above it. This does in fact allow you to provide the same cooling with warmer air, although whether that winds up saving energy depends on the details of how the cooling system is designed and controlled.The key to displacement ventilation is to inject the air into the space at very low velocities (50FPM, rather than 200-400 FPM as in a standard mixing system), so that it does not mix. But this means that your diffuser area goes up significantly, which increases costs and architectural hassles.The other problem is that displacement works great in cooling, but it works against you in heating, because all the warm, unmixed air winds up stuck to the ceiling. Typically this means that you have to have a separate heating system (e.g. radiant floors).

I've seen several comments complaining about the "negative tone" of this article. I am sorry to say this, but that negative tone is entirely justified and appropriate. This building is, by any real measure, "light green" at best and greenwash at worst (hard to say more precisely without seeing the design details).I am personally extremely invested in creating buildings which use dramatically less energy, are better for their occupants, and support rather than destroy natural ecological function. That's why I do this work, now (I used to be in aerospace). So it frustrates me to see these light green buildings treated as something revolutionary when they are not.Don't get me wrong - even the light green buildings are often (though certainly not always) better than average. The LEED system has driven very important innovations in the building sector. But from the perspective of real sustainability, better than average doesn't mean much, because the average is so very, very poor. LEED's version of green is at best a way to be "less bad". That's better than "more bad" but it is not the same thing as being "good".

What constitutes "good" in this context? The Living Building Challenge is far from perfect, but it comes closer than any other standard I know to defining parameters for a truly sustainable building.

So, as a professional HVAC engineer who is really into (actually) green buildings, I feel compelled to provide a reality check:

- The energy claims of this building are based on models, not on actual performance. As anyone who works with computer models of any sort can tell you, models can and will lie to you. Diligence and skill are required to avoid that outcome. If there is an incentive to produce a certain result, then that caveat goes double.

Reminds me of the quote I heard in LEAN training... "All models are wrong. Some are useful." Very true.

I work in a green building that has the floor ducts. The first few years we were in the building, the average temperature on my floor was 65-67, while other floors hovered around 85. It's finally some better; my floor is usually around 71, while the warmer floors are below 80. And this is in a region where summer temperatures can stay above 100 for weeks on end.

This building isn't in what I'd call suburbia. It's in the University Towne Center (UTC) area of San Diego - the city's largest central business district (more office space than downtown SD I believe). There are still a lot of people who commute to work here by car (this is southern CA after all) but there is a lot of medium density housing nearby if you wanted to live close to work. Lots of condo towers, 5-6 story apartment buildings, townhouses, etc. There are almost no single-family detached homes (one tiny pocket of homes) in the UTC area. A major research university (UCSD) and lots of research institutes, hospitals, biotech/pharma and wireless telecomm companies are also here.

Displacement ventilation, on the other hand, DOES work if properly implemented...The key to displacement ventilation is to inject the air into the space at very low velocities (50FPM, rather than 200-400 FPM as in a standard mixing system), so that it does not mix....But this means that your diffuser area goes up significantly, which increases costs and architectural hassles.

Probably one reason this approach hasn't been universally adopted, given the distinct possibility that the savings don't actually live up to the promises (as you discuss in your post).

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The other problem is that displacement works great in cooling, but it works against you in heating, because all the warm, unmixed air winds up stuck to the ceiling. Typically this means that you have to have a separate heating system (e.g. radiant floors).

Luckily, it sounds like this building is going to be built across the highway from La Jolla.